A new species and new records of Laelaspis Berlese (Acari, Laelapidae) from Iran

Abstract This paper reports on three species of mites of the genus Laelaspis in Iran – Laelaspis calidus Berlese from Pheidole pallidula, Laelaspis humeratus (Berlese) from Tetramorium caespitum and Laelaspis dariusi Joharchi & Jalaeian, sp. n. fromsoil. The new species is described and illustrations provided.


Introduction
The Laelapidae is one of the largest families of free-living Mesostigmata, but it has not yet achieved a stable classification (Tenorio 1982, Joharchi et al. in press). Hypoaspis Canestrini and related genera have had an especially complicated and confusing history, including Laelaspis Berlese, 1903, which has often been treated as a subgenus of Hypoaspis Canestrini, 1884(Hunter 1961, Hunter and Glover 1968, Karg 1982, 1993, Faraji et al. 2008. Joharchi et al. (2011) treated Laelaspis as a separate genus, and gave a diagnosis and comparison of diagnostic characters for the closely related genera Gymnolaelaps and Pseudoparasitus. That concept of Laelapsis is followed here. Joharchi et al. previously reported on five species of mites of the genus Laelaspis and on several genera associated with ants in Iran (Joharchi et al. in press, Joharchi et al. 2011). Joharchi et al. have previously provided a key to species of Laelaspis occurring in the Western Palaearctic Region with a summary of their host associations and biology (Joharchi et al. in press). We now expand the study to include further species in the genus Laelaspis Berlese, 1903, mainly associated with ants and soil.
The cosmopolitan genus Laelaspis includes 17 species in the Western Palaearctic Region and most species are associated with ants or their nests. However, a few were collected with small mammals or in soil, and most species have only been collected on few occasions, so it is difficult to draw any firm conclusions about their host specificity (Joharchi et al. in press). Six species of Laelaspis have been reported previously from Iran (Joharchi et al. in press). Unidentified species of Laelaspis were also reported from Iran by Kamali et al. (2001) and Nemati and Babaeian (2010). The purpose of this paper is to describe another species of Laelaspis and increase our knowledge of the Iranian fauna of Laelapidae.

Materials and methods
Mites associated with ants and soil were collected in Alborz, Khorasan, Kerman and Yazd Provinces over a period of two years (2010)(2011)(2012). Mites were removed from ants' nests by individual hand picking and by extraction from ant nest and soil material using Tullgren funnels. Mites were cleared in Nesbitt's solution and mounted in Hoyer's medium. The nomenclature used for the dorsal idiosomal chaetotaxy is that of Lindquist and Evans (1965), the leg chaetotaxy is that of Evans (1963a) the palp chaetotaxy that of Evans (1963b), and names of other anatomical structures mostly follow Evans and Till (1979). We use the term "lyrifissures" to refer to slit-shaped sensilli, and "pore" for circular or oval-shaped cuticular openings of unspecified function. The holotype and paratypes of the new species are deposited in the Acarological collection, Department of Plant Protection, Yazd Branch, Islamic Azad University (YIAU); paratypes are also deposited in the Jalal Afshar Zoological Museum, College of Agriculture, University of Tehran, Iran (JAZM) and in the Australian National Insect Collection, CSIRO Ecosystem Sciences, Canberra, Australia (ANIC). All measurements in the descriptions are given in micrometres (µm).
Diagnosis. See Joharchi et al. (2011). Notes on the genus. Laelaspis belongs to a group of genera of Laelapidae in which the genital shield of the female is greatly expanded, so that its posterior margin abuts the anal shield and its lateral margins extend outward behind coxae IV. The expanded genito-ventral shield in these genera captures at least two pairs of ventral setae in addition to the genital setae on the the extreme edges of the shield. Laelaspis is distinguished from Gymnolaelaps by its two-tined palp tarsal claw, the absence of pre-sternal shields, and the presence of two distinct Λ-shaped lines on the genital shield. Laelaspis differs from Pseudoparasitus because Pseudoparasitus has at least two pairs of setae on the surface of the genital shield, well separated from the edges of the shield, while all the genital setae of Laelaspis and Gymnolaelaps are on the extreme edges of the shield. Notes. Laelaspis calidus was described from east Africa (Berlese 1924), also has been recorded at Kilimanjaro near Marangu from moss and litter (Aswegen and Loots 1970) and has not been reported since. It is easily recognised by the bidentate movable digit and the seven-toothed fixed digit, the serrated postanal seta and seta Z5 two to three times as long as J5. This species has been found from moss and litter, but has not been reported from the nests of ants. It is now recorded in Iran for the first time from the ant nests.
Insemination structures not seen, apparently unsclerotised. Etymology. The species is named in memory of Darius I (Old Persian: Dārayava(h)uš), also known as Darius the Great, was the third king of the Achaemenid Empire, who proved to be a strong and wise ruler and he was tolerant toward other religions and cultures, promoted learning, agriculture, forestation, and the construction of highways. He also built the great palace cities of Susa and Persepolis.

Laelaspis humeratus
Notes. Laelaspis humeratus was described from Luxemburg (Berlese 1904), and has been recorded from Latvia (Lapina 1976;Salmane 2001aSalmane , 2001b, Russia and Austria (Bregetova 1977), and England (Hull 1925;Evans and Till 1966). This species was found associated with at least two genera of ants (Lasius and Tetramorium), freeliving in soil, litter and meadows, and from the nests of mammals. This species is easily recognised by the large number of long, thick and wavy opisthonotal setae, the bidentate movable digit and the tridentate fixed digit. Haddad Irani-Nejad et al. (2003) recorded an unidentified species as Laelaspis near humerata (Berlese, 1904), but the identity of that species cannot be confirmed because the specimens have been lost, so this is the first record of L. humeratus from Iran.

Discussion
Before the start of this study, six species of Laelaspis had been reported from Iran. We have added new information on L. calidus and L. humeratus.
Joharchi et al. have previously discussed the distinction between Laelaspis and Gymnolaelaps and Pseudoparasitus (Joharchi et al. 2011). The biology of most species of Laelaspis has not been studied, but the limited information that is available shows that they are predatory (Hunter 1964). Laelaspis appears to be a genus of predators that feed on other small invertebrates in their hosts' nests, but are not harmful to the ants. High populations of acarids may be harmful to ants, so the presence of predators such as Laelaspis may be beneficial, forming a symbiotic relationship with its ant hosts. The ecological role of Laelaspis in mammal nests is also unknown, but it appears likely that they are predators, feeding on other nest inhabitants such as acarid mites (Rasmy et al. 1987).